Over the last six years we have offered behavioral treatment to young autistic children (children less than 46 months of age if echolaic, 40 months of age if mute). The children have been randomly assigned to two groups, a Treatment I group receiving more than 40 hours of treatment per week and a Treatment II group receiving less than 10 hours per week. Pre-treatment assessment include psychiatric/neurological evaluations, psychological testing, behavioral recordings, diagnostic checklists, etc. Treatment is modelled on a behavior modification framework, including parent training. Post-treatment measures are carried out after the child has reached six years of age, and include the child's ability to function independently in, and adequately adjust to and learn from, normal school placement. To date we have 20 children in Treatment I, and 12 children in Treatment II. Preliminary data suggest a recovery rate exceeding 50% in Treatment I group, compared to a 0% recovery rate in Treatment II. Funds are requested for an additional two years so as to complete treatment of the last children in both groups and to complete follow-up evaluations.